Is the questioner accountable for a portion of the sin of his friends who still listen to songs he previously recorded and distributed to them, and what should he do about it?

Songs accompanied by musical instruments (ma'azif) or those performed by women are forbidden. Indicating or assisting in sin is forbidden, due to the Almighty's saying: (And cooperate in righteousness and piety, but do not cooperate in sin and aggression) [Al-Ma'idah: 2], and due to the Prophet's (PBUH) saying: (Whoever calls to misguidance will bear the sin thereof like the sins of those who follow him). One must repent from indicating and spreading sin, and advise friends to stop listening to forbidden songs.